Numeric control milling machines and engine lathes are both well known devices in the machine tool art. A typical numeric control milling machine may cost $45,000 and up and a numeric control lathe may cost $35,000 and up.
The objective of this invention is to impart numeric conrol lathe capability to an otherwise convential milling machine with only relatively slight increase in cost for the added components, which cost increase may be approximately onetenth of the cost of a seperate numeric control lathe.
According to the invention, the above objective is obtained by mounting a lathe head and chuck of a conventional manually controlled engine lathe and the coacting lathe tail stock on the translational table of a numeric control milling machine. In so doing, the structure of the milling machine is not altered, reformed or defaced in any way and the mill retains its full original capability as a separate machine tool.
Additionally, a lathe turning tool and its holder are securely mounted in fixed relation to the mill table and the rotating work by clamping to the stationary bed structure of the milling machine, whereby in the subsequent turning or machining of the work piece, the latter is moved with the mill table relative to the stationary tool rather than vice-versa as is customary in all engine lathes, whether manual or numeric control types.
In a sense, therefore, the invention comprises a comparatively simple and inexpensive lathe attachment means or "kit" for a costly numeric control milling machine. In a broader sense, the invention comprises an improved numeric control mill which has the capabilities of a numeric control engine lathe without the necessity for a user or a manufacturer to possess both costly machines. Instead, by means of the invention, the possessor of a numeric control mill may acquire the lathe capability by an expenditure of about one-tenth the cost of acquiring a numeric control engine lathe.
Various features and advantages of the invention will appear to those skilled in the art in the course of the following description.